Sri Lankan monarchs were rulers of the island nation of Sri Lanka from ancient times until the colonial period. The monarchy played a significant role in the island's history, with notable kings such as Devanampiya Tissa, who embraced Buddhism in the 3rd century BCE, and Parakramabahu I, known for his contributions to infrastructure and agriculture in the 12th century. The last monarch was Sri Vikrama Rajasinha, who ruled until the British annexed Sri Lanka in 1815. The monarchy was characterized by a complex system of governance, with kings often supported by a council of ministers and local chieftains, reflecting the island's rich cultural heritage.